The present invention relates to a method of forming a synthetic image in a simulation system for attachment of spectacles. Namely, the invention relates to a method of forming a synthetic image in a simulation system for spectacles by making an image of a person as if wearing a given pair of spectacles from an image of a person not wearing a pair of spectacles and by displaying the synthetic image to enable the person to try on and select a new pair of spectacles.
Currently, when a person desires to buy a pair of spectacles at a place where they are sold, in order to see the state or appearance of his face with the frame of the spectacles in place, in the case of selecting a desired frame of spectacles not containing prescription lenses, he directly tries on a given frame of a pair of spectacles not containing lenses, and observes his face reflected by a mirror.
However, in the case of persons of strong near-sightedness, astigmia, or the like, the image becomes dim even at a position which is fairly close to the mirror when the person removes his own spectacles to try on just the frame of a new pair of spectacles to be selected. Therefore, such a person cannot correctly know the state of his face when he wears only the frame of the spectacles. To solve this drawback, as a simulation system for attachment of spectacles in which the state of the face as if wearing spectacles can be known, a system disclosed in U.S. Pat. No. 4,730,260 to Mori et al, corresponding to JP-A-61-80222, has been proposed. This method uses the image synthesis processing technique. An image of a person who has removed his own spectacles is picked up by a video camera. An image pickup signal of this person's image is A/D converted into a digital signal. This digital signal is stored into an image memory device. A display signal which is derived by synthesizing the data of the person's image stored in the image memory device and the data of a frame of spectacles to be selected is formed. The state in which this person wears the spectacles is displayed by the display apparatus, thereby allowing a preferable pair of spectacles to be selected.
In this system, when a person's image is stored, the person's image picked up by the video camera is displayed by the display apparatus and the video camera is operated such that the face of the person comes to the position at which the frame of the spectacles will be displayed and thereafter, a person's image as if wearing the spectacles is picked up.
This is because when the image of the frame of the spectacles is made, if its size, position, and angle are preliminarily fixed, it is sufficient to use a computer having a small capability. Therefore, a square frame indicative of the position of the frame of the spectacles is displayed by the display apparatus. The display signal of this square frame and the image pickup signal from the video camera are synthesized and displayed. The video camera is moved while observing the display image in a manner such that the portion of the face on which a pair of spectacles is arranged by simulation just enters this square frame. Thereafter, the person's image as if wearing the spectacles is picked up by the video camera. By this method, there is no need to correct the data of the frame of the spectacles in accordance with the size, position, and inclination of the face. It is sufficient to provide a computer of small capability.
Further, according to this method, the data of the frame of the spectacles is transferred to the image memory device from another memory device and synthesized.
An image of a person whose spectacles have been removed is picked up. The person who uses a pair of spectacles to correct eyesight removes the spectacles and observes the display image on the display apparatus. In this case, he cannot clearly observe the image because the image becomes dim. Thus, the person cannot match the frame of the spectacles with his face on the display apparatus by himself.
On the other hand, even in the case of a person whose eyesight is relatively good, when he looks at the image of the display apparatus while facing generally toward the video camera, since the video camera and the display apparatus are not arranged at the same position, his face will have been picked up in a state in which the direction of the line of sight is not in front of the video camera.
Further, in general, when a person faces in front of the camera or the like and is photographed in this state, his face is not horizontally still but has a tendency such that the face is slightly inclined to the right or left. Therefore, when the synthesized image is displayed by the apparatus to match spectacles, even if the size or position (inclination) of the frame of the spectacles is slightly deviated, i.e. slightly rotated or moved, the person feels a physical disorder. The display image may fairly differ from the image which is derived when the person puts on the actual frame of the spectacles. It is difficult to display an accurate synthetic image of the person's image and the frame image of the spectacles.
Further, according to the method disclosed in said U.S. Pat. No. 4,730,260, since the person's image must be correctly displayed within a range of the designated screen, in order to pick up an image of a person, the video camera must be moved to match the size and position of the person's image. Thus, another person who photographs a person's image or a remote controller capable of adjusting the photographing position and angle and the like is necessary.
Namely, in order to insert the face whose image is picked up into the range of the frame at the position of the frame of the spectacles on the screen of the display apparatus, the size of the face must be made coincident with the fixed position on the display screen.
For this purpose, it is necessary to perform correct and fine adjustments such as to move the photographing means such as a video camera or the like back and forth or to the right and left, or the like. Its adjusting work is complicated and it takes extra time to adjust.